Stitching device

ABSTRACT

A stapling device is usable to staple printed products transversely to their direction of travel in a folding machine of a rotary press assembly. There is no relative movement between the stapling heads and the product sections during stapling. The stapling heads move directly radially to the counter cylinder during the stapling operation.

FIELD OF THE INVENTION

The invention relates to a stapling device for transverse stapling ofproduct elements, in particular in a folding apparatus downstream of arotary printing press.

Description of the Prior Art

DE 29 32 757 C2 describes a stapling device in a folding apparatus of arotary printing press. In this case a combined cutting and staplingcylinder is provided with female and male molds, which shape staples.The male mold is moved by means of a four-bar link.

It is disadvantageous in connection with this stapling device thatduring the stapling process the staple performs a relative movement inthe circumferential direction in relation to the collecting cylinder andthe product elements. This can result in damage of the products andpulled-out stapled connection.

EP 06 06 555 A1 describes a rotating stapling apparatus with staplingheads arranged in a star shape. These stapling heads are pivotable andwork together with supports fixed in place on a collecting drum. It isdisadvantageous here that the stapling heads perform a back-and-forthmovement, so that large acceleration forces are required.

A stapling device is known from U.S. Pat. No. 2,727,383. In this device,a stapling head, which is capable of swinging back-and-forth, cooperateswith a counter support fixed on the cylinder.

EP 05 20 967 A1 discloses a stapling device wherein the stapling heads,as well as the counter supports, are respectively rotatingly arranged onseparate cylinders. It is disadvantageous here that the counter supportis rotatingly arranged on a cylinder.

SUMMARY OF THE INVENTION

It is the object of the invention to provide a stapling device fortransverse stapling of product elements, wherein in the course of astapling process a staple does not perform a relative movement in thecircumferential direction in respect to the product elements to bestapled or respectively to a counter cylinder.

In accordance with the invention, a stapling cylinder is provided withstapling heads which are arranged to work with a counter cylinder thatis provided with staple closure beds. The stapling heads point in thedirection of the axis of rotation of the counter cylinder during thestapling process. The stapling cylinder or cylinders are disposed on arotating stapling cylinder support. The speed of rotation of thestapling cylinder approximately corresponds to a sum of the rotationalspeed of the stapling cylinder support plus the rotational speed of thecounter cylinder.

The advantages which can be attained by means of the invention primarilyconsist in that relative movements of the staples vertically in respectto the stapling movement in relation to the product elements orrespectively to the opposed closure beds are avoided to a large degree.By means of this bending stresses acting on the staples and the opposedclosure beds are reduced. This stapling movement generates a greatstapling quality, since the tearing of the staple out of the productelements is prevented. By means of the optimized stapling movement it ispossible to staple product elements which, in comparison to the priorart, are thicker, or respectively more layers of product elements, aswell as to achieve higher production speeds. Furthermore, the loadacting on the stapling device because of vibrations is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS

The stapling device in accordance with the invention is represented inthe drawing and will be described in more detail in what follows.

Shown are in:

FIG. 1, a schematic lateral view of a stapling device in accordance withthe invention;

FIG. 2, a schematic sectional view of the stapling device in accordancewith the invention;

FIG. 3, a schematic representation of an enlarged portion of a movementprogression in the course of a stapling process in accordance with FIG.1.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

In side frames 1, 2 of, for example a folding apparatus of a rotaryprinting press, a cutting and stapling cylinder support 3 and acollecting cylinder 4 acting as counter cylinder 4 are seated, rotatablein the same direction around their parallel extending axes of rotation6, 7, as may be seen in FIG. 1. In the instant exemplary embodiment(FIGS. 1 to 3), the cutting and stapling cylinder support 3 is providedwith two rotatable cutting cylinders 8, 9 as well as two rotatablestapling cylinders 11, 12, whose axes of rotation 13, 14, 16, 17 arearranged, offset in pairs by 180°, concentrically at a radius r3, forexample r3=300 mm, in respect to the axis of rotation 6 of the cuttingand stapling cylinder support 3. In this case the cutting and staplingcylinders 8, 9, 11, 12 are offset by 90° in respect to each other. Inthe course of a cutting or respectively stapling process the cutting andstapling cylinders 8, 9, 11, 12 turn in the opposite direction inrespect to the collecting cylinder 4. Three cutters 18, extendingparallel with the axes of rotation of the cutting cylinders 8, 9, arefastened in each of the latter and are offset by 120° in respect to eachother, and their cutting edges 19 are arranged at a radius r19, forexample r19=150 mm, concentrically in respect to the axis of rotation13, 14 of the respective cutting cylinder 89. The stapling cylinders 11,12 are constructed in the same way, therefore the following descriptionis restricted to one stapling cylinder 11. Three staple levels 21,respectively offset by 120° and extending parallel with the axes ofrotation 16 of the stapling cylinder 11 are provided in the latter, inwhich a plurality of stapling heads 22, in the instant example two, arefastened in the axial direction.

Essentially each stapling head 22 consists of a die 23, fixed in placein respect to the stapling cylinder 11, 12, and a spring-loaded radiallymovable stapling piston 24. On their outward pointing end, the staplingpistons 24 are provided with two cutting and guide elements 26. Acamshaft 27 acts on an inwardly oriented end of the stapling piston 24.This camshaft 27 is seated in the center of the stapling cylinder 11 androtates at rpm of n27, which exactly corresponds to rpm n3 or awhole-number multiple of the rpm n3 of the cutting and stapling cylindersupport 3. The camshaft 27 is designed in such a way that while thestapling wire is transferred, the stapling piston 24 is extended and,following the completed stapling, i.e. in a center line 28 of thecutting and stapling cylinder 3 and collecting cylinder 4, is completelyretracted. A bending horn 29, for example an eccentric one, isrespectively arranged around the stapling cylinders 11, 12 in theinterior of the cutting and stapling cylinder support 3 in the area ofthe stapling heads 22. A distance of the interior surface 31 of thebending horn, extending parallel with the axis of rotation 16 of thestapling cylinder 11, to the axis of rotation 16 of the staplingcylinder 11 is reduced in the direction of rotation of the staplingcylinder 11, for example by means of an eccentric arrangement of thehollow cylinder-shaped, segment of a circle-shaped bending horn 29, oran interior surface 31 of the bending horn embodied in a helical shape.The bending horn 29 is continued at each end outside of the jacketsurface of the cutting and stapling cylinder support 3 in the form oftwo resilient sheet metal pieces 32, 33. These resilient sheet metalpieces 32, 33 leave only a narrow gap between their facing ends.

The collecting cylinder 4 is used as the counter cylinder for thecutting and stapling cylinders 8, 9, 11, 12 and therefore is providedwith cutter bars 34 fixed in place on the cylinder and opposed closurebeds 36 fixed in place on the cylinder. Respectively three cutter bars34 and opposed closure beds 36, offset by 120°, have been cut,congruently with a jacket surface 37 of the collecting cylinder 4 with aradius r4, for example r4=300 mm, concentrically in respect to the axisof rotation 7 of the collecting cylinder 4, wherein the cutter bars 34and the opposed closure beds 36 are offset by 60° in respect to eachother.

The drive of the cutting cylinders 8, 9 and stapling cylinders 11, 12,as shown most clearly in FIG.2, is performed by means of a planetarytoothed gear, starting at a main drive toothed gear train. To this endthe collecting cylinder 4 has a toothed wheel 38 with a number of teethz38, for example z38=132, which is driven by a drive, not represented.For driving the cutting and stapling cylinder support 3, an intermediatetoothed wheel 39 with a number of teeth z39, for example z39=64, whichis seated in the side frame 1, engages this toothed wheel 38 of thecollecting cylinder 4, and in turn cooperates, by means of anintermediate toothed wheel 40, with a second intermediate toothed wheel41 with a number of teeth z41, for example z41=64, which is seated inthe side frame 1. This second intermediate toothed wheel 41 meshes witha toothed wheel 42 with a number of teeth z42, for example z42=88, ofthe cutting and stapling cylinder support 3, so that the cutting andstapling cylinder support 3 rotates at n3 rpm.

A toothed wheel 43 with a number of teeth z43, for example z43=39, isconnected with the intermediate toothed wheel 41 and engages a toothedwheel 44 with a number of teeth z44, for example z44=33, which is seatedfreely rotatable concentrically in respect to the axis of rotation 6 ofthe cutting and stapling cylinder support 3. Two sun wheels 46, 47 withteeth on the exterior and with a number of teeth z46, for example z46=72or respectively z47, for example z47=96, are connected with this toothedwheel 44. A planetary toothed wheel 48 with a number of teeth z48, forexample z48=60, of the camshaft 27 of the respective stapling cylinder11, 12 meshes with the first toothed sun wheel 46, and a planetarytoothed wheel 49 with a number of teeth n49, for example n49=36, of therespective cutting cylinder 8, 9 meshes with the second toothed sunwheel 47.

On the opposite side of the cutting cylinders 8, 9 a second,obliquely-toothed planetary toothed wheel with a number of teeth z51,for example z51=52, is fastened on the cutting cylinder 8, which engagesa freely rotatable toothed sun wheel 52, also obliquely-toothed, with anumber of teeth z52, for example z52=78, which is concentrically seatedin respect to the axis of rotation 6 of the cutting and staplingcylinder support 3. This toothed sun wheel 52 is rigidly connected witha second, obliquely-toothed sun wheel 53 with a number of teeth z53, forexample z53=78, and both toothed sun wheels 52, 53 are together axiallydisplaceable by means of an actuator drive 54. The second toothed sunwheel 53 meshes with a toothed planetary wheel 56 with a number of teethz56, for example z56=52, of the respective stapling cylinder 11, 12, sothat the stapling cylinder 11, 12 rotates at n11 rpm. The obliquesurfaces of the teeth of the toothed sun or planetary wheel 52, 51 ofthe cutting cylinders 8, 9 are unequal to the oblique surfaces of theteeth of the toothed sun or planetary wheel 53, 54 of the staplingcylinder 11, 12, because of which a phase shift between the cuttingcylinders 8, 9 and the stapling cylinders 11, 12 can be performed. Bymeans of this the stapling can be matched to a lower or upper fold.

The cutter bars 34 or respectively the opposed closure beds 36 of thecollecting cylinder 4 work together with the cutters 18 of the twocutting cylinders 8, 9 or respectively the stapling heads 22 of the twostapling cylinder 11, 12. For this reason the rpm n3 of the cutting andfastening cylinder support 3 must be 1.5 times the rpm n4 of thecollecting cylinder 4, i.e. n3=1.5×n4. In order to achieve anapproximately radial orientation of the cutters 18 or respectively thestapling heads 22 in respect to the collecting cylinder 4 during cuttingor respectively stapling, the rpm n8 of the cutting cylinders 8, 9 orrespectively an rpm n11 of the stapling cylinders 11, 12 is a sum of theamount of the rpm n3 of the cutting and stapling cylinder support 3 andthe amount of the rpm n4 of the collecting cylinder 4, i.e.n8=|n3|+|n4|, or respectively n11=|n3|+|n4|. With the mentioned radiir3, r4 an approximately equal circumferential speed of the cutters 18 orrespectively the stapling heads 22 and the cutter bars 34 orrespectively the opposed closure beds 36 during cutting results.

A staple wire feeding device 56, not shown in detail, is disposed,offset by 144° in the direction of rotation of the cutting and staplingcylinder support 3 in respect to the center line 28 of the cutting andstapling cylinder support 3 and the collecting cylinder 4, at theperiphery of the cutting and stapling cylinder support 3. At thislocation, the stapling head 22 performing the next stapling is at itsgreatest distance from the axis of rotation 6 of the cutting andstapling cylinder support 3, i.e. the stapling head 22, the axis ofrotation 16, 17 of the stapling cylinders 11, 12 and the axis ofrotation 6 of the cutting and stapling cylinder support 3 are located ona common straight line. A high section of the camshaft 27 presses thecutting and guiding elements 26 against a spring force sufficiently faroutside, that the corresponding, maximally occurring radius of thecutters 18 is exceeded. In this way a U-shaped female die for bendingthe staple is formed by means of the fixed die 23 and the extendedcutting and guide elements 26. A stapling wire is fed to the cutting andguide elements 26 of the stapling head 22 and is subsequently cut off bythe continuing rotating movement of the cutting and stapling cylindersupport 3. Immediately following the completed cut, the cut-off wire isbrought underneath the first--viewed in the direction of rotation--resilient sheet metal piece 32 by the continuing rotating movement ofthe stapling cylinders 11, 12. In this way the stapling wire is fixed inthe cutting and guide elements 26. The stapling wire is conducted intothe area of the bending horn 29 by the continuing rotating movement ofthe stapling cylinders 11, 12 with the stapling heads 22. Because of thedecreasing distance of the inner surface 31 of the bending horn 29 inrespect to the axis of rotation 16 of the stapling cylinder 11, thestapling wire is pushed into the U-shaped female die formed by the die23 and the cutting and guide elements 26 and is therefore shaped into astaple during the rotating movement of the stapling cylinder 11. Theshaping of the staple is terminated at the latest prior to the exit outof the bending horn 29, in the instant example approximately after a180° rotating movement of the stapling head 22 in the bending horn 29.At least until this time the high area of the camshaft 27 presses thestapling piston 24 with the cutting and guide elements 26 outward.Thereafter the formed staple is held by the second resilient sheet metalpiece 33, which continues the bending horn 29 in the direction ofrotation. The camshaft 27 rotates from its high into its low area inrelation to the stapling piston 24. In the process the stapling piston24 with the cutting and guide elements 26 moves radially inward andpartially releases the staple legs of the staple. At the latest shortlyprior to the contact of the staple legs with the product elements 57,the respective stapling heads 22--and therefore also the staples--extendradially in respect to the axis of rotation 7 of the collecting cylinder4. The entire stapling movement is performed by the superimposedradially rotating movements of the stapling cylinder 11, 12 and thecutting and stapling cylinder support 3 in respect to the axis ofrotation 7 of the collecting cylinder 4. By means of the rotatingmovement of the cutting and stapling cylinder support 3, the staple ispushed into the product elements 57 by the fixed dies 23, which act onthe back of the staple. As soon as the staple is moved by the productelements 57, the cutting and guide elements 26 are completely retractedand the staple leaves the second resilient sheet metal piece 33. Thestaple penetrates the product elements 57 and is closed by the opposedclosure beds 36 which are provided, for example, with oat grain-likedepressions.

To perform the described stapling process, the stapling cylinders 11, 12and therefore the stapling heads 22 rotate around their respective axesof rotation 16, 17. This rotating movement is performed by means of thedescribed drive in such a way that the respective staple head 22, whichparticipates in the actual stapling process, performs an approximatelyradial rotating movement oriented to the axis of rotation 7 of thecollecting cylinder 4 at least from the start to the finish of thestapling process, i.e. from the contact on the product elements 57 tolifting off the product elements 57, as is depicted in FIG. 3. In theprocess, the participating stapling heads 22 as well as thecorresponding opposed closure beds 36 move at the approximate speed ofthe web.

In place of the described planetary gear, other drives can also beemployed for performing the rotating movement of the cutting andstapling cylinders 8, 9, 11, 12. It is conceivable, for example, torotate the cutting and stapling cylinders 8, 9, 11, 12 directly by meansof electric or hydraulic motors synchronized with the cutting andstapling cylinder support 3.

The stapling cylinder 11 can, of course, also be seated in its own,rotating stapling cylinder support separated from the cutting cylinders8, 9.

The device in accordance with the invention is not limited to therepresented exemplary embodiment with a three-part collection cylinder4, but can also be adapted to other cutting and stapling devices with,for example, five- or seven-part collecting cylinders.

While a preferred embodiment of a stitching device in accordance withthe present invention has been set forth fully and completelyhereinabove, it will be apparent to one of skill in the art that anumber of changes in, for example, the type of printing press, the typeof product web being printed, the overall structure of the foldingdevice, and the like could be made without departing from the truespirit and scope of the present invention, which is accordingly to belimited only by the following claims.

What is claimed is:
 1. A stapling device usable to transversely stapleproduct elements in a folding apparatus portion of a rotary printingpress assembly, said stapling device comprising:a stapling cylinder; aplurality of stapling heads on said stapling cylinder; a countercylinder having staple closure beds, said staple closure beds beingarranged to cooperate with said stapling heads, said counter cylinderhaving an axis of rotation and being rotatable at a counter cylinderspeed of rotation, each said stapling head pointing toward said countercylinder axis of rotation during stapling of the product elements; astapling cylinder support having a stapling cylinder support axis ofrotation and being rotatable at a stapling cylinder support speed ofrotation; and means for supporting said stapling cylinder on saidstapling cylinder support for rotation about a stapling cylinder axis ofrotation and for rotating said stapling cylinder at a stapling cylinderspeed of rotation, said stapling cylinder speed of rotationcorresponding to a sum of said counter cylinder speed of rotation plussaid stapling cylinder support speed of rotation.
 2. The stapling deviceof claim 1 wherein said means for rotating said stapling cylinderincludes a planetary toothed gear wheel.